1 general:: Suppress, as in He choked back his tears. [Late 1800s]
American Heritage Idioms
2 general:: Phrase(s): choke something back to fight hard to keep something from coming out of one’s mouth, such as sobs, tears, angry words, vomit, etc. • I tried to choke the unpleasant words back, but I could not. • She choked back her grief, but it came forth nonetheless. • I could hardly choke my tears back.
McGrawhill's American Idioms And Phrasal Verbs